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Re: Torosaurus NOT Triceratops



Yes, of course. By miscode i meant due to interpretation, 
perhaps affected by poor preservation, or otherwise 
inadvertently. I didn't mean deliberately, e.g. to try 
to get a particular result! Of course, choosing 
characters is itself subjective. 

I have also seen characters that are plainly erroneous 
which appear to have been coded based on published 
figures or perhaps simply on what someone else wrote. 
Yes it's hard to travel around the world (or country)
and personally examine all relevant specimens, and yes, 
it should be possible to rely on published descriptions, 
but that risks compounding any misinterpretations. 

I also notice that my original msg (below) somehow got 
truncated. It should have ended "...seems to me a more 
likely scenario than one big, happy taxon." 
(or something like that)


--- On Thu, 3/1/12, Ralph Chapman <ralphchapman@earthlink.net> wrote:

> From: Ralph Chapman <ralphchapman@earthlink.net>
> Subject: Re: Torosaurus NOT Triceratops
> To: turtlecroc@yahoo.com, dinosaur@usc.edu, Michael.OSullivan@port.ac.uk
> Date: Thursday, March 1, 2012, 3:06 PM
> 
> You should probably make it amazingly
> clear what I'm really pretty sure you actually mean - that
> by miscode what you really mean is that in their work they
> made choices that others might/would interpret differently
> in coding these characters, perhaps because they (the
> characters that is) need much more data or study and/or may
> be really tough to interpret/code. You are not saying they
> chose to do so on purpose. We've had odd times in the past
> where a few individuals seemed to casually suggest people
> misrepresented data on purpose and that, of course, without
> massive proof is reprehensible. I presume you mean the
> former and not the latter but correct me if I'm wrong.
> 
> Ralph
> 
> 
> -----Original Message-----
> >From: Paul P <turtlecroc@yahoo.com>
> >Sent: Mar 1, 2012 1:41 PM
> >To: dinosaur@usc.edu,
> Michael.OSullivan@port.ac.uk
> >Subject: Re: Torosaurus NOT Triceratops
> >
> >--- On Thu, 3/1/12, David
anovic@gmx.at>
> wrote:
> >
> >> > Am I the only one who thinks that the dataset used for the determination
> >> > of Torosaurus as a valid genus, or something synonymous with
> >> > Triceratops, is capable of being used to support either view...
> >> 
> >> Yes. It's not who analyses the data, but whether enough
> >> methods are used.
> >
> >Um, actually, no. The data in this paper can be used to 
> >argue that they're separate taxa OR to argue that Toro. is 
> >Triceratops, just like you can pretty much show anything
> >you want using many published character matrices. All you 
> >have to do is miscode one or two key characters for one
> >or two key specimens. Note the asterisks in Longrich and
> >Field's table. Statistically, i think that table/data 
> >shows that Torosaurus *is* Triceratops just as much as 
> >it shows the opposite. The more immature specimens are 
> >skewed toward Triceratops while the most mature are skewed 
> >toward Toro. I know that doesn't prove anything, but it's 
> >statistical. 
> >
> >My hunch is that Torosaurus is valid, at least *some* 
> >Toros. In the end they may all prove to be synonymous, 
> >but what about those Toros in UT? Just a sampling issue?
> >And what about immature chars in some Toro skulls? John
> >Scannella and the MOR group have tried to address that 
> >using histology, but the dataset is still incomplete. 
> >As Denver says (i think), it's unfortunate that many of
> >the older but well preserved skulls don't have detailed
> >stratigraphic data with them, but they are still useful.
> >They're not just heads floating in space or whatever. 
> >
> >All dinosaurs are morphotaxa (er, all *extinct* dinos),
> >so sample size is crucial. There is a lot of circularity
> >in trying to separate individual variation from ontogeny
> >from taxonomy from dimorphism in similar taxa. You can 
> >apply the tools, but in the end, it's largely statistical. 
> >I think in a year or two you will see someone arguing 
> >that Toro is the mature form only of *male* Trikes. 
> >Despite Ho

> >me a more likely 
> >-- On Wed, 2/29/12, Michael OSullivan <Michael.OSullivan@port.ac.uk>
> wrote:
> >
> >> From: Michael OSullivan <Michael.OSullivan@port.ac.uk>
> >> Subject: Re: Torosaurus NOT Triceratops
> >> To: bcreisler@gmail.com,
> dinosaur@usc.edu
> >> Date: Wednesday, February 29, 2012, 6:45 PM
> >>
> >> Am I the only one who thinks that the dataset used
> for the determination
> >> of Torosaurus as a valid genus, or something
> synonymous with
> >> Triceratops, is capable of being used to support
> either view, depending
> >> on who's analysing the data. I think there's a real
> danger of
> >> subjectivity obscuring the reality. Whatever the
> hell that is...this
> >> rate, Torosaurus will be revealed to be a late
> living Stegosaur
> >> ---
> >> 
> >> Michael O'Sullivan
> >> 
> >> Palaeobiology Research Group
> >> Postgraduate Student
> >> School of Earth & Environmental Sciences
> >> Burnaby Building
> >> Burnaby Road
> >> Portsmouth
> >> PO1 3QL
> >> 
> >> Email:michael.osullivan@port.ac.uk
> >> >>> Ben Creisler  01/03/12 12:10 AM
> >> >>>
> >> From: Ben Creisler
> >> bcreisler@gmail.com
> >> 
> >> 
> >> A new paper in PLoS ONE:
> >> 
> >> 
> >> Longrich,  N.R. & Field, D.J. (2012)
> >> Torosaurus Is Not Triceratops: Ontogeny in
> Chasmosaurine
> >> Ceratopsids as a Case Study in Dinosaur Taxonomy.
> >> PLoS ONE 7(2): e32623.
> >> doi:10.1371/journal.pone.0032623
> >> http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0032623
> >> 
> >
> 
> 
> Ralph E. Chapman
> Paleontologist & Technologist
> New Mexico Virtualization
> 102 El Morro St.
> Los Alamos, NM 87544
> USA
> (505) 672-2240 [Home]
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> ralphchapman@earthlink.net
>